To date we have treated 32 patients on this study and have attained the maximum dose level of 0.96 mg/kg. Toxicity consisted of capillary leak for which patients were pre-treated with a COX-2 inhibitor. Additional toxicity consisted of nausea, vomiting, diarrhea and fatigue. The maximum tolerated dose appears to have been reached at 0.096 mg administered on day 1, 4, 8, and 11. All patients demonstrated anti-PE40 antibodies by time of completion of drug.